Aerial propulsion apparatus



Feb. 26, 1946. R GODDARD 2,395,404

AERIAL PROPULS ION APPARATUS Filed Oct. 18, 1939 4 Sheets-Sheet 1 Feb.26, 1946; H, GODDARD 2,395,404

AERIAL PROPULSION APPARATUS Filed Oct. 18, 1939 4 Sheets-Sheet 2 g m 7'08/ druid m2 A Feb.26, 1946. R H, G DAR 2,395,404v

AERIAL PROPULS ION APPARATUS Filed Oct. 18, 1939' 4 Sheds-Sheet s f 9 lr @1150 (/20 Feb. 26, 1946.

H. GODDARD AERIAL PROPULSION APPARATUS Filed Oct. 18, 1939 4Sheets-Sheet 4 b mzeigza ad er the non-rotating nut or Patented Feb. as,1946 invention type miopulsion apparatus for aircMt IWhlchisprovidedwith one or more bladed propellers 1H8 the'gen'eral Object of improvedmeans by which gases discharged from rocket-type combustionapparatusmayl be directis utilized in the rotation 01 aircraftpropellers, whether or not I said "propellers are normally driven fromsome othersourcejoi' power.

An important feature of the. invention relates to the utilization forcombustion gases from rocket-type apparatus in a {turbine associatedwith an aircraft propeller. Ialso provide rockettype combustionapparatuswhich is directly associated with and rotatable with thepropeller of an aircraft. a g 1 My invention further relates toarrangements and combinations of parts which will'be hereinafterdescribed and more particularly pointed out intheappendedclaims. j a

A preferred iorm of the invention is shown inthedrawingainwhich I Fig. 1is a plan view 01 the iorward portion an airplane having 'myimprovementsembodied therein; p v

Fig. 2 is a front elevation; looking in the directionotthearrcwlinnml; i

- Fig.3isaperspectiveviewoi apropellerblade:

Fig. 4 is a view illustrating the onerasonoimyinvmflw: ,1 i a Fig. 5comprises a of partial sectional elevations, takenalong lines'a'.lacanddn spectively in Fig. 4;

Flss.6and7arefi'ontelevatlonsotcertain fixed valve or shut-oi! to bedescribed;

Fig.- 8 is a secflonal view. taken suhstantiallyalongthelineHinl 'igA;

Fig. ilisaswtion'alplanviemtakenalongthe Iinel-linl'ig.8; ff i Fig. 10is a perspectiveviewot a male to be described;

Fig. llisanenhrledsecflonalp tspecflveview of the rotatmg partsotmyimproved propulsion apparatus; a

Fig. 12isanenlargedsectionalperspectiveview the propulsion loparatlu.the section lI-ltinFigJ; Fig. l2isane1flargeddetailsecticnalviewofcertainpartsappearingjhrriggm: filzliiisanenlarged' view oiportions V ofand = mnussmunenmsidsleievmmm theiuelinletsina;

substantially along the ll-f-ll and ilk-ll cowling coversto bedescrlbed;

mm devices to be described;

16 is a perspective view of a irontcasg P rtion tobedescribedrt Figs.1'1, ,18and 19 are sectional views. partly in perspectiveshowingdevicesior adjusting certain Fig. 20 is a detail perspective view,looking-in the direction oi the arrow 28 in Fig. 12; t and Fig. 21 is a-plan view 01 certain sealing 22 is an enlarged perspective view of thefiring devicesshown in Fig. 21; v

22isaticviewoianelectrical firing circuit to be described;

Fig. 23 isa further enlarg d perspective view or certain details shownin Fig.22;

Fig. 24 is a atic lay-out of certain cam and firing details;

Fig. 25 is a sectional elevation of the fuel feeding and liquidsealingdevices; Fig.25isapartialtransversesectionalviewoIasealingmernbentakenalnngthe line'iF-il in Fig. 25; a i

Fig.26isanenlargedsectionsldetaiLtaken along the line "-2! in Hg. 25;

Fig. 2'! isanexplodedviewotcertainpartsoithesealingdeviceetobedescribed;

Fig. 27'- is a transverse sectional view showins Fig. 2'2;

Figs.28,29andSOareperspectiveviewsoiadditi'csial.detaihoithescalingdevices;

as. l'lmuisanenlarged sectionalviewctcerhin partsshowninHI-JG;

rig.32isanenlargedpartialandappiollmately longitudinal sectional view orone unit or my improved propulsion apparatus;

4 'FIgJBisacsectionaIYieIM- a Beforedescribimthedetailsofconstructionota NQIMAGQ-ilitled Rovsmber 13.11984, b 't dlfmy improved propulsionapparatus, I will state briefly the construction and method of operationthemot. v Hy improved apparatus, while capable of some-"mwhatgeneralapplicatiomisparticularlydeskned'tompplyauxiliarypowertoa'prope'llerinanaircrsitatsuchtimesasmorepowerisgos'desirable. Accordingly.thepropulsionapps,- V

thepropcll risnormallyrotatedrli mg fl thism m a 1min cutainf pointsmsmlarity to the-apparatus shownin' nm thelei'l relationottl'iepartsshmminfering largely therefrom both in construction application. a 7

My improved propulsion apparatus is mounted in a streamlined annularcasing. positioned at the front of an aircraft cowling and supported byand rotatable with the aircraft propeller.

As the rate of disc gases from rocket apparatus is much too high for anddirect and efficient application to propeller blades, 7 I providesuccessive series of non-rotating turbine blades and turbine bladesassociated with the propeller, by the coactlon of which the energy ofthe combustion gases may be-more effectively applied to increase thespeed or power of said propeller.

Auxiliary power may be supplied to the propeller continuously or forsuch periods of time as-may be desirable, and provision is made forclosing off the air intakes and thus minimizing the air resistance whenthe apparatus is not in use, it being understood that my auxiliarypropulsion apparatus rotates with the propeller, whether or not lt-ls inuse to develop additional power. v

Referring to Figs. 1 and 2. I have shown the front end portion of thecasingor cowling C of an aircraft having a propeller shaft so pro-.vided with a'propeller ll having" blades 4 2 and harge of thecombustion The number of such combustion units is preferably equal tothe number of propeller blades, with an air-collecting chamber "providedin the rotated front casing portion it between each two adjacentpropeller blades 42, as indicated in Fig. 4. Single valve plates 62 andu serve all of the combustion units.

Each collecting chamber is is'disposed at an angle in the front casing58. In order to provide streamlined air entrance to the chamber, theforward part of the chamber. is formed with the successive crosssections shown at a, b, c and d in Fig. 5, these sections being takenalong the lines a, b, c and d in Fig. 4 respectively.

normally rotated by a suitable engine or motor,

indicated at ll (Fig. l). The front end of the shaft has the usualstreamllnedcasing Each of the blades 42 is of the usual flattened .ovalor' elliptical cross section, and is. provided with a portion 48 ofcircular cross section intermediate its ends. This circular sectionpermits a blade-to be swiveled about its longitudinal axis to vary thepitch, while at the same time the blades may provide support for therotatable auxiliary propulsion apparatus.

a between 'the chambers" and is are opened and The inner or rear endofthe air-collecting chamber to (Fig. 83) rotates closely adjacent thenon-rotating valve" or shut-oil plate il-(Flg.

6) which is ,provided'with elonsatedslots'll and -withrelativelyshort-shut-oif portions II. The

air--collecting chamber." is open intothe combustion chamber '3 so longas a slot 10 is interposed between the chambers, and the entrance end ofthe combustion chamber is closed, when .a BhlltsOfl portion II isinterposed between the chambers.

Liquid fuel, preferablyhydrogen, is injectedin 4 spray form through theopenings. ti 'nearlthe contracted rear end of each'air-collectlng'ch'ainto its asso-.

ber and adjacent-its connection ciated combustion chamber. as. a

The non-rotating shut-off plate l4 is positioned at the rear or exitend-of each of the combustion chambers 68 and isprovidedwithr'elativelyshort slots or openings 13 (Fig. 7)Jcorrespending with the shortvalve'or shut-oflportions ll of the plate II. The valve plates :2 and Nare so related angularly that the openings closed simultaneously butreversely with the openings between the chambers zles it, as clearlyshown in Fig. 33.

The rapid motion of my propulsion apparatus through the air, due both torotation of'the apparatus and to forward progress of the aircraft,together with the described operation of the shut-oil plates 62 and 64,causes surging of the air in the chambers 80 and it and strongoscillations of pressure, all as explained in detail in ing the innerside of the casing, and a rotated annular streamlined front casingportion 58.

These casing parts are all madeof a light strong' alloy and the part Itwill preferably be reduced in thickness toward its rear edge to preventdistortion, as shown in Fig. 11. The non-rotating parts of the casingare mounted on streamlined arms or brackets 54 (Fig. 1) fixed to thecowling my prior Patent No. 1,980,266 above cited. The

Parts are so timed that when the compression of the mixture of air andliquid fuel within the combustion chambers has substantially reached itsmaximum, the intake openings will be closed,

the passages to the nozzles will be opened, and

C, and the rotated parts have u p rting bear-' j logs on the propellerblade portions 43.

V Combustion apparatus My improved rocket type combustion apparatus isshown tically inrig. 4, in sectlon in l 'lg. 32, and ingreater detail onSheet 2 of the drawings. The axis of the propeller shaft ll isindicatedbythe dot-and-dash centerlina' in Fig. 4. Each combustion unitcomprises a a to be described by which the explosions in each unit perrevolution may be reduced to two or even the charges will beiired byspark-plugs II (Fig. vide three explosions for each revolution of thepropeller ll, but! have also provided mechanism one.

a cape at very high speed and provide a reaction rotating air-collectingchamber llv (Figs; 4' and 32) having ruel inlets ii; a non rotatingannular valve or shut-off plate u, a rotating combustion chamber II, asecond non-rotating valve or shutolf plate is, a rotating dischargenozzle 06, a

series of non-rotating turbine blades It, a series or rotating turbineblades I1, and a secondseries v of non-rotating turbine blades-ll.-

- impulse partly ln'thedirection of the arrow a:

or to the left in Fig.1 and also partly rearward.

As the gases. leave the nollel l, they encounter thewseriesofnon-rotating blades II by which they'are redirected in'the directionof rotation of the propeller. The gase then encounterthe series ofrotating blades ll, thus giving a further forward impulse to thePropeller with which they rotate. On leaving the rotating blades II,

the gases encounter the second series of non-rotating blades it by whichthey are directed rearward as indicated in ii, after which they'es- Nand theme-.-

, Ordinarily, each combustion unit will pro The combustion eases fromeach nozzle ll es-1 cape from the non-rotated m 'rherzrleserlbed theliquid issupplied mm a WWW r1 closed m n mim-f; creaseai theliemieriey Mv sure which ma ybedevel oped bylt's'own V greater than thepropellenlanes, n enasaiaim new "Fwy Jones to the reduced portions 4:, wherethepassa'ges 44 cate with hie iuel feed openings 6 I.

or theaircrait; A it thereiorecresuite asth eaetgr inned"deben" pairs,with certain openings at w (Fig. distion. The is preferablyjenclosed Min or jacket W Q evaporation of the hydrogen. ,L'Ihe nycmea a Qdelivered-through a pipe ll (Figs. arena to. I asealing device 8 (P18-21) from whichiit leech-f1, anct dtnrou n a pipe Ii (Fi 25). alongsidethe) propeller shaft II to the passages 44 (Fig.3? ex-l" I tendingaxiaily'through the propeller-blades l2,

communicate with'annular conduits 82' .(Figj13), which surround thecontracted inner ends ofthe air-collecting chambers and whichicom muni-These'openings II are preferably arranged in upon the diflelence Plfisfiuares of the-initial posed at a rather wide angle to produce awidely on xed a narrower spray. Preferably the wide andnarcircumferential wall of the collecting chamber more forcibly injectedtoward the middle of the contracted'passage.

stantial advantage. as I thus avoid the serious projectinginto the airstream at 'the high air is a particularly desirable fuel for my nimproved propulsion apparatus. However, liquid hydrogen is vnot onlyvery light but is also extremely cold, so that it is impossible to use asealing lubricantjor a solid packing; either of which would immediatelyfreeze. It is accordingly necessary to Jacket all parts containingliquid hydrogen with liquid air or liquid oxygen but the liquid hydrogencannot be directly exposed to the liquid air or oxygen as, being at muchlower temperature, it will immediately freeze the Jacketing liquid anditself evaporate it direct contact is permitted.

'"In order to overcome these dlfllculties, I provide a double mercuryseal which balances the hydrogen pressure automatically andprevents-leakage between two telescoping rings, one of which is fixedand the other supported by and rotating with the propeller shaft 40. i

v if Dre ent' cons there are'n reativelyfheavy moving pa sistthequickiorceoI the explosions Thejreiative'ly'light wel'ghto! thisiuelis ale, advantageous on account .or the comparatively; smallexpenditure of energy necessary "to give the '1 with the" propellershaft 40 and communicates grained liquid an seous v fuel itsrapldforwarcli with the-pipe" previously described. Bothmemq orrotational speed asit'is delivered to thecbmvhers 81 and PM are ofsubstantially U-shaped gtustiojn i anit rs'jwni h otajtejwit j the p pller. 1 section. The'gase hichpass through thellllIbineparts. The flowof hydrogen from the pipe to the are lar ely em t lirj fh t pgen irornthetintal ce ipe at is controlled by annular slotted valve scatteredspray and with other openings as Bi (Fig. 15') disposed at a smallerangle to produce 4 row sprays are alternated around the contracted 50. Avery even'distribution and excellent atomizatlon is thus secured, as thewidely scattered".

sprays are largely taken .upvnear the outer wall of the chamber, whilethe narrower sprays are This method of introducing liquid fuel is ofsub- I losses which would be occasioned by any. parts busflbn as Aspeeds and high densities encountered in the con-u accountot its lightwelghtand high heat value,

Thesealing device 8 comprises a flxed housing qwlth liquid-oxygen fromany convenient source. ;At. its ln'nerend the hydrogen feed pipe 86.com-

municateswith a fixed annular member 81 (Fig. 27) which-has a loosesliding fit within a second annularrfimeinber 88 which is fixed to androtates.

inside of the member .1 (Fig.2?) while the other rotates with themember88, The slots in the valve members 80 and Si normally coincide so thatfree hydrogen fiow takes place, except at such times as the shut-oi!plate 82 closes the passage between the air-collecting chambers I andthe combustion chambers 83.

Discs 94 (Figs. 25 and 29) are fixed to the rotating propeller shaft 40and extend outward within the sealing casing 8|. These discs areprovided with radial vanes 90 on their outer sides. which vanes runclosely, adjacent the inner end races of the fixed casing 88. Additionaldiscs or (Figs; 25 and 28) are fixed to the fixed outer casing and areprovided with radial vanes 9| which are preferably somewhat wider thanthe fixed vanes 88. The outer edges of the vanes 9| are closely a jacentthe rotating discs 94.

Additional short vanes 99 (Fig. 29) are secured gmembersllandti(Pig.2'l),oneoiwhichisfixed.

to the inner-sides of the rotating discs 84 and Id and extend closelyadjacent the outer sides or the fixed discs 91. The housing or casing 08is to be partially filled with a heavy liquid M, preferably mercury,which is caused by centrifugal torce to occupy the annular space outsideof the lines M-M in Fig. 25 when the apparatus is operating at normalspeed.

As the axis or the propeller shaft ll is normally horizontal, themercury will collect in the "bottom of the casing II when the propellershaft is at rest, most of it being between the relatively wide fixedvanes so. when the propeller is rapidly rotated, the mercury will moveoutward under centrifugal force produced by the rotating vvanes I, butwill not move inward toward the rings a and a, due to the action of theshort vanes it. A ring Ill (Fig. 29) connecting the outer ends or theshort vanes It prevents loss of energy ,by eddies between moving andstationary portions of mercury.

This is due to the fact that two streams of liqtend to intermingle andthus produce a large energy loss by the formation of eddies. The

ring III prevents this loss as the liquid moving ing rings .1 and llwill thus be automatically attained, with just suliicient'mercury forcedout around the discs it to balance the hydrogen gas pressure. It will benoted that the hydrogen, it any, which escapes from the-casing ll willbe in the tormoi gas and will have been suiliciently warmed initspassage through the casing ll so that there will be no danger offreezing the surrounding atmosphere.

The use of mercury for a liquid seal is of advantage. as it isover 190times as heavy as liquid hydrogen and consequently'a liquid seal-o! verygreatly reduced diameter can be used. Furthermore, it is unnecessary tojacket the casing It as would be necessary if liquid hydrogen were usedin the seal.

rotate adjacent the inner ends oi the fixed vanes v mercury. vtoprovideworkingpresh asitevapocateswillnottreelethe Assoonastheliquidbydrogenhasdevice Smay be'enlarg d a y. 8M

1m construction 1th my not only to provide eilective sealuid moving incontact but in opposite directions 1 .E 7 outwardsentotbe'iacketspacesoitberotatilsparts.

was is mimiiedunder v m (Fig. 2:) may be provided int'heme tiltomcreasethscentriiussl i'crceaisocausesthe oxygen to iiowaliottheiscketspacelin the tubes H0 surroundhw thc hydrogen passages Man to thdr dhcsandsetsoivanesmaybeemwiththeannuiarpsssager It thecontracted portions plate m.

6 ciated propulsion apparatus, which revolution moves the star wheelspast the relatively ilxed This causes the star wheels to be advanced oneI tooth for each revolution of the propeller shaft and associatedmechanism, thereby gradually closing the covers Ill. The star wheels aresimultaneously moved toward the right in Fig. 19 by the threadedbearings thereof, so that the teeth of the star wheels willveventuallyclear the right-handjend of theplate Ill, and the 1zcfivers ll! willremain in adjusted closed posi- When it is thereafter desired to openthe covers ill for further operation of the propulsion app ratus. theframe I8! is shifted in the opposite direction to bring the plate ill toposition to engage the star wheels and intermittently rotate the same inthe opposite direction to slide the covers 852 to the open position ofFig. 2.

Operation The general operation of my improved propulsion apparatus hasbeen quite fully indicated in the detailed. description but may bebriefly as follows:

. peiler, the valve or shut-oil plates .2 and it alternately close theair-collecting chambers ill and the combustion chambers it, and theexplosive charges are fired when the combustion chambers are closed attheir intake ends and Open at their discharge ends to the nozzles Bl.The discharge gases pass successively through the fixed turbine bladesII, the rotating blades l1, and the iixed discharge plates II, thussupplying powerto the ring or band I! (Fig. 11) and to the propeller 'onwhich said head is -mounted.

The power supplied may be varied by the settins of the valve In whichregulates the flow of fuel to the combustion chambers. The frequency ofthe explosions is determined by the setting of the contact am it! (Figs.22 and 23) as described, and may provide either one, one and one-half.or three explosions-per revolution for each combustion chamber.

It should be particularly noted that I have to a very great extentavoided use of relatively movin: parts in my improved apparatus; Inparticular, the operation oi the valve plates 82 and I depend solelyupon rotation of the propeller and not upon additional mechanicalconnections.

By the provision of turbine blades to be used in connection with thedischarge gases of rocket apparatus. I greatly improve the eiilciency ofsuch apparatus and provide apractical means to uti- 9,89li,d0d

Theconstrlctedpartoftbeeollectingebmnber,

ll, where the spray orliices are located, is of advantage inseverabrespects: it reduces the distance through which thesprays have totravel:

itincreasesthespeedoftheairatthispoint.

and hence produces increased atomimticn: and it further-reduce the area,and consequentlythe force, over which the gases exert pressure onthevalve plate 82 during the explosions.

Having thus described my invention and the advantages thereof, I do notwish to be limited to the details herein disclosed, otherwise than asset forthin the claims, but what I claim is:

1. In an aircraft, propulsion apparatus comprising a noted member, powermeans to rotate said member, an annular casing rotatable with said valvemeans automatically controlling communication between said openings andsaid chambers during rotation and operation thereof, and additionalmeans to open and close said air-intake openings for interruptingoperation thereof while said casing and chambers are in rapid rotation.

2. in an aircraft. propulsion apparatus comprising a rotated member,power mean to rotate said ,member, an annular casing rotatable with saidmember, a plurality of rocket type combustion devices mounted in saidcasing and rotatable therewith in a path spaced radially andsubstantially outward from but concentric with the axis of rotation ofsaid member, and means to apply the combustion gasesescaping from saiddevices to the production of increased power to rotate said 4 member,said casing having spaced air intake openings in its front portiondirectly exposed to the slip-stream of air about said craft when inflight, covers for said air-intake openings mounted on said casing forcircumferential sliding moveso ment thereon. and manualLv-controlledmeans to elfectopening or closing circumferential movements of saidcovers while said casing is in rapid lire such rocket apparatus forsupplementing the power of a rotating propeller.

It not particular importance that the air for against the direction offlightto the combustion chambers.

My invention may be applied to standard types of aircraft with butlittle necessary modification.

rotation. v

8. The combination in an aircraft as set forth in claim 2, in whichautomatic means is provided to limit said opening and closing movements.

4. In an aircraft, propulsion apparatus comprising a rotated member.power means to rotate said member, rocket-type combustion devicesrotated with said member in a path spaced radially and substantiallyoutward from but concentric with the axis of rotation of said member.means to directly utilize the combustion gases escaping from saiddevices to supply additional power to turn said member, each combustiondevice comprising a combustion chamber and an air-collecting chamber.both mounted at a substantial and common angle to their common path ofrotation,

collecting chambers and of said combustion chambers respectively andhaving spaced circumferential slots and interposed shut-oil! portions,said plates being fixed in such angular relation that theysimultaneously and reversely open and close the intake and dischargeends of each of said combustion chambers as said chambers rotaterelativeto said plates.

5. In an aircraft, propulsion apparatus comprising a rotated member,power means to rotate said member, rocket-type combustion devicesrotated with said member in a path spaced radially and substantiallyoutward from but concentric with the axis of rotation of said member,and means to directly utilize the combustion gases escaping from saiddevices to supply additional power to turn said member, each combustiondevice comprising a combustion chamber and an air-collecting chamber,both mounted at a subof rotation, and said collecting chamber beingeffective to directly collect air from the slip-stream in said chamberand said air being compressed insaid collecting chamber by the highspeed rotation of said chamber in said angular position, eachair-collecting chamber having means to produce fuel sprays substantiallythroughout the cross section between said aircollecting chamber and itscoacting combustion chamber, and said means comprising alternately andcircumferentially disposed wide-angle and to the productionof increasedpower to rotate said member, firing means for said devices, and manusally selective means to vary the total number of per revolution of saidmember or three times during each two successive revolutions of saidmember.

prising a rotated member, power means to rotate said member, rocket typecombustion devices rotated with said member in a Path spaced radiallyand substantially outward from but concentric with the axis of rotationof said member, means to directly utilize the combustion gase escapingfrom said devices to supply additionaljpower to rotate said member,means to supply air to said stantial and common angle to their commonpath devices, means including fixed and rotating parts to supply liquidfuel undenpressure to said devices while said devices are in rapidrotation, and a means to prevent escape ofsaid liquid fuel in saidsupply means between the fixed and rotating parts thereof, said lattermeans'including fixed and rotating adjacent discs, vanes onsaid discs,and

a quantity of mercury interposed between said discs and vanes andsealing said fuel supply means.

10. In an aircraft, propulsion apparatus comprising arotated member,power means to rotate said member, rocket type combustion devicesrotated with said member in a path spaced radially and substantiallyoutward from but concentric with the axis of rotation of said member,means to directly utilize the combustion gases escaping from saiddevices to supply additional power to rotate said member, means tosupply air tosaid devices, means including fixed and rotating parts tosupply liquid fuel under pressure to said de vices while said devicesare in rapid rotation, and means to prevent escape of said liquid fuelin said supply means between the fixed and rotating parts thereof, saidlatter means including fixed and rotating adjacent discs, relativelywide vanes on said fixed discs, relatively narrow vanes on said movingdiscs, and a quantity of-a heavy liquid interposed between said discsand vanes and,

largely retained by said wide vanes when said rotated member is at restwith its axis approximateignitions Der revolution of said rotatedmember;

while maintaining an equal number of ignitions Per revolution for eachand every combustion device.

prising a rotated member, power means to rotate said member, an annularcasing rotatable withsaid member, a plurality of rocket type combustiondevices mounted in said casing and rotatable therewith in a path spacedradially and substantially outward from but concentric with the axis ofrotation or said member, means to app y the combustion gases escapingfrom said devices to the production of increased power to rotate said.said member, a plurality of rocket type combustion devices mounted insaid casing and rotatable therewith in a path spaced radially andsubstantially outward from but concentric with the axis of rotation oisaid member, means to apply the combustion gases escaping from saiddevices to the production of increased power to rotate said member, andmanually selective means to fire each and every device either once orthree times '7. In an aircraft, propulsion apparatus com-- 1yhorizontal.

11'. In an aircraft having propulsion apparatus comprising a rotatedmember, powermeans to rotate said member, an annular casing rotatablewith said member and having spaced air-intakecombustion chambers.

openings in its front portion which are directly exposed to theslip-stream of air about said craft when in fiight, a plurality ofrocket type combustion' devices mounted in said casing and rotatabletherewith in a path spaced radially and substantially outward from butconcentric with the axis of rotation of said members and means to applythe combustion gases escaping from said devices to the production ofincreased power to rotate said member, that improvement which comprisesan air-collecting chamber for each combustion device rctating therewithbut spaced axially there- 7 from and coacting with an associated intakeopenins, a nozzle device rotating with each combustion chamber andassociated therewith but spaced axially thererfom, and fixed valve meansbetween said spaced parts which automatically control communicationbetween associated air-collect-- ins and combustion chambers and betweeneach combustion chamber and its associated nomle during rotation andoperation thereof, whereby the gaseous content of each combustionchamber is successively compressed, ignited and released and in timedrelation to the operation of the other ROBERT E. counsel).

